The death toll from mudslides and flooding in the Dominican Republic and Haiti soared to around 2,000 last night as rescuers discovered more than 1,000 bodies in a ruined Haitian town.

The border region between the two Caribbean countries, which share the island of Hispaniola, has been devastated by water and mudslides which have engulfed the area after 10 days of heavy rain. Entire villages have been swept away by a vast tide of mud miles long and several hundred metres wide.

Haitian officials said more than 1,000 bodies were discovered in Mapou, a remote town near the border that was all but destroyed. Another 500 people were killed elsewhere in south-eastern Haiti and 158 in the riverside town of Fond Verettes. Some 300 bodies had been recovered in the Dominican Republic, with hundreds more still missing.

The death toll makes the disaster the worst on the island for more than a generation. More than 800 died in a tropical storm which caused flooding in Haiti 10 years ago, while in 1998 a hurricane killed 229 in the country. More than 1,000 people were killed, most of them in the Dominican Republic, in a 1979 hurricane.

"The rain came," said Manie Ceceron, destitute after the devastation in Fond Verettes and the loss of her five children. "I was in the house and I ran. I couldn't see anything. I didn't see my children. I never saw my children."

The catastrophe struck in the early hours of Monday when villagers in the two impoverished countries were still asleep. Rivers swollen by the heavy rains burst their banks and surged through set tlements, destroying hundreds of houses and sweeping off victims. Some bodies were carried several miles.

The floodwaters sent thousands of tonnes of rocks and sediment through some villages. The death toll was particularly high because Haiti is 90% deforested, and poor people on both sides of the border mostly live in wooden shacks.

In Fonds Verettes the flooding swept away the tax office and courthouse.

Only half of the police station remained, Reuters reported. The Haitian justice minister and acting interior minister, Bernard Gousse, said: "We are sending shelters and food supplies to affected areas."

Troops from a US-led multinational force sent to stabilise Haiti after Jean-Bertrand Aristide, the president, was ousted three months ago, flew into the hard-hit Haitian towns yesterday, taking bottled water, medicines and food.

"It appears there have been many victims that have been washed out of the village or may be buried underneath the rubble," said Colonel Glen Sachtleben, the chief of staff of the multinational force.

In the Dominican Republic, President Hipolito Mejia declared a day of national mourning for Thursday.

One man, Jude Joseph, who had gone to Jimani, the worst affected town in the Dominican Republic, from Haiti's capital, Port-au-Prince, to sell rice at a border market and visit family members in Bobmita, La Cuarenta and Barrio El Tanque, found all those neighbourhoods swept away. "I've been left with nothing," said the 30-year-old, whose nine relatives were still missing. Another resident, Norma Cuevas, was desperately looking for her 63-year-old mother along with dozens of other families searching for signs of life.

José Luis German, a spokesman for the Dominican Republic's national emergency commission, said relief workers were continuing to claw through the mud looking for survivors, aided in the search by sniffer dogs.

Although many of the bodies have been identified, dozens of unidentified victims have been buried in mass graves.